JPS63201469A - Cooling-output measuring device for cooling device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Problems to be solved by this invention When measuring the cooling output of a cooling device that cools a medium to be cooled, such as water or antifreeze in a water tank, conventionally, the cooling output, that is, the cooling heat Measure the temperature drop per hour (cooling curve) of the object to be cooled (cooled medium, water tank, piping, etc.) as m, and for example, if you ignore the heat capacity ports of tanks and other heat capacity, use the following formula (%).Q: Cooling Amount of heat, T: Temperature gradient, ■=Volume of the object to be cooled Cp
The amount of cooling heat was calculated by substituting each numerical value for: specific heat of the body to be cooled, and q: specific gravity of the body to be cooled.

However, when a refrigerator is used as a cooling source, its cooling output changes depending on the temperature of the object to be cooled, and as shown in Figure 3, the temperature difference between the cooling source and the object to be cooled changes as the temperature drops. In the case where the cooling curve gradually decreases, the temperature gradient T changes depending on each temperature, so the temperature gradient T at the temperature to be measured had to be sequentially determined by drawing a tangent to the cooling curve. Furthermore, during cooling when a refrigerator is used, the pressure and temperature inside the piping are constantly changing, so the actual cooling output of the cooling device when the refrigerator is operated steadily at a certain temperature is There was a problem in that the temperature gradient T obtained by the equation did not match the value calculated by substituting it into the above calculation formula.

In addition, measurement and management of V, Cp, and q of the object to be cooled is complicated, and there are many uncertain factors such as a delay in the temperature reached due to differences in heat transfer rate between the object to be cooled and the water tank, piping, etc. However, there was a problem in that it was extremely difficult to measure the correct cooling output (cooling heat amount).

The present invention provides a new measuring device that solves these problems.

<Structure of the Invention> The present invention is an output measuring device for a water tank and a cooling device that cools a medium to be cooled in the tank, the output of which is a heating heater that controls the output to a constant set temperature of the medium to be cooled. A cooling output measuring device for a cooling device is characterized in that it performs replacement measurement by measuring the amount of heat.

<Example> Examples will be described below based on the drawings.

Cooling system! consists of a refrigerator 2 and a water tank 4 containing a medium 3 to be cooled such as water or antifreeze, and as shown in FIG. In addition to the storage type, any type of structure may be used, such as a circulation type in which the refrigerator 2 and the water tank 4 are connected through a pipe. Note that 5 in the figure is a stirrer for making the entire temperature of the medium 3 to be cooled uniform.

The cooling output measuring device 6 includes a continuous proportional control temperature controller 9, which is formed by connecting a temperature sensor 7 and a heating heater 8 outside the device through connection lines 7a and 8a, respectively, and a temperature controller 9 that is used for heating. An effective value converter 10, ti that detects the voltage/current supplied to the heater 8 and converts it into an effective value, and each converter 10.11
The calculator 12 is configured to calculate the amount of heat of the heating heater 8 according to the signal value sent from the calculator 12, and the display unit 13 digitizes and displays the numerical value calculated by the calculator 12.

The continuous proportional control temperature controller 9 has a circuit configuration shown in FIG. 2, and an error amplifier 9a detects and amplifies the unbalanced voltage between the temperature sensor and the temperature setting switches a-a' due to the feedback effect of the temperature sensor 7. Then, the triac roll call circuit 9b that receives the amplified signal value continuously and variably supplies the current to the heating heater 8 from 0% to #100% to control the temperature of the cooling medium 3 with high precision. Unlike temperature controllers that control the temperature by repeatedly turning ON and OFF a constant power supply, or time proportional control systems that supply 6 stages of power, the power required for temperature control is constant regardless of time. In this case, the heating heater 8 is energized.

The temperature sensor 7 and heating heater 8 of the cooling capacity measuring device r16 configured as described above are set in the water tank 4 of the cooling device 1 in which the refrigerator 2 is in a steady state, and the temperature of the measuring device 6 is adjusted. The temperature of the cooling medium 3 is controlled at a constant temperature by setting the device 9.

The effective value converter 10.11 calculates the voltage and current supplied to the heating heater 8, and calculates the amount of heat of the heating heater 8 using the following calculation formula: Heater Mffi (Kcallo) = P (Kll)
x 860 (KCa'/n, xv) = I rms (
A) X Eras (V) Mowing 60 (K”/II-KW)
P: heater power, I: heater current, ■: heater voltage.

oo(Kcallo-o): Heater heat amount ff1(
The amount of heat of the heating heater 8 is measured by the calculator 12 set with the calculation function of the constant), and the measured value (heater heat fi
t) is digitized and displayed on the display section 13.

When the temperature of the cooling medium 3 is controlled with high precision, the fluctuation in the amount of heat applied by the heating heater 8 is small and becomes almost constant, and at this time, the amount of heat applied by the heating heater 8 and the cooling device l
Based on the principle that the cooling output of the cooling device 1 is in equilibrium, the amount of heat of the heating heater 8 digitally displayed on the display unit 13 can be read as a numerical value representing the cooling output of the cooling device 1 at that temperature. be.

Note that the display unit 13 may be an analog display instead of a digital display, and a recorder (chart) 14 may be arranged in parallel to save records.

In addition, when measuring the cooling output of a constant temperature device equipped with a temperature control device including a heating heater, the temperature control function must be stopped or the power supply to the heating heater can be continuously proportional The desired purpose can be achieved by a simple switching operation performed by a controlled temperature regulator.

<Effects of the Invention> As described above, the measuring device of the present invention not only eliminates the long measurement work required by the conventional actual measurement calculation method, but also eliminates the need for the type and amount of the cooled medium and many other uncertain factors. The effect is that the cooling output of the cooling device can be measured accurately and easily without being affected. Furthermore, since the refrigerator is operated in a steady state, it is easier to compare and examine the data specific to the refrigerator and the data in the installed state, which has the effect of streamlining the inspection and maintenance work of the cooling system. .

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the state of measurement of cooling output by the apparatus according to the embodiment of the present invention, FIG. 2A is a circuit diagram of a continuous proportional control temperature controller, and FIG. 2B is a diagram of the current controlled by the controller. Waveform diagram, Figure 3 is a graph diagram showing an example of a tangent line drawn to obtain a temperature gradient from a cooling curve actually measured using the conventional method, 1 is a cooling device, 2 is a refrigerator, 3 is a medium to be cooled, and 4 is a water tank. , 5 is a stirrer, 6 is a cooling output measuring device, 7 is a temperature sensor, 8 is a heating heater, 9 is a continuous proportional control temperature controller, 10 is a voltage effective value converter, 11 is a current effective value converter 12 is a computing unit, 13 is a digital display section, and 14 is a recorder.

Claims (1)

[Claims] (1) An output measuring device for a water tank and a cooling device that cools a medium to be cooled in the tank, the output measuring the amount of heat of a heating heater that controls the medium to a constant set temperature. A cooling output measuring device for a cooling device, characterized in that the cooling output is measured by replacement.